Por favor, use este identificador para citar o enlazar este ítem:
http://cicese.repositorioinstitucional.mx/jspui/handle/1007/1703| Geochemistry and Geochronology of the Guajira Eclogites, northern Colombia: evidence of a metamorphosed primitive Cretaceous Caribbean Island-arc | |
| Marion Weber | |
| Agustin Cardona Victor A Valencia Uwe Altenberger MARGARITA LOPEZ MARTINEZ Marin Sebastián Judy Marcela Zapata Henao Elena Perdomo | |
| Acceso Abierto | |
| Atribución-NoComercial-SinDerivadas | |
| http://dx.doi.org/10.1344/105.000001740 | |
| Eclogites, Primitive island-arc, Geochronology, Guajira Peninsula, Colombia, Caribbean | |
| "The chemical composition of eclogites, found as boulders in a Tertiary conglomerate from the Guajira Peninsula, Colombia suggests that these rocks are mainly metamorphosed basaltic andesites. They are depleted in LILE elements compared to MORB, have a negative Nb-anomaly and flat to enriched REE patterns, suggesting that their protoliths evolved in a subduction related tectonic setting. They show island-arc affinities and are similar to primitive islandarc rocks described in the Caribbean. The geochemical characteristics are comparable to low-grade greenschists from the nearby Etpana Terrane, which are interpreted as part of a Cretaceous intra-oceanic arc. These data support evidence that the eclogites and the Etpana terrane rocks formed from the same volcano-sedimentary sequence. Part of this sequence was accreted onto the margin and another was incorporated into the subduction channel and metamorphosed at eclogite facies conditions. 40Ar-39Ar ages of 79.2±1.1Ma and 82.2±2.5Ma determined on white micas, separated from two eclogite samples, are interpreted to be related to the cooling of the main metamorphic event. The formation of a common volcano-sedimentary protolith and subsequent metamorphism of these units record the ongoing Late Cretaceous continental subduction of the South American margin within the Caribbean intra-oceanic arc subduction zone. This gave way to an arc-continent collision between the Caribbean and the South American plates, where this sequence was exhumed after the Campanian." | |
| Universitat de Barcelona | |
| 2011 | |
| Artículo | |
| Geologica Acta, Vol. 9, Págs. 425-443 | |
| Inglés | |
| Weber,M.B.,Cardona Molina,A.,Valencia,V.A.,Altenberger,U.,López Martínez,M.,Tobón,M.,Zapata Henao,S.,Zapata,G.,Concha,A.E.2011.Geochemistry and Geochronology of the Guajira Eclogites, northern Colombia: evidence of a metamorphosed primitive Cretaceous Caribbean Island-arc.Geologica Acta,9,425-443.doi:10.1344/105.000001740 | |
| GEOLOGÍA | |
| Versión publicada | |
| publishedVersion - Versión publicada | |
| Aparece en las colecciones: | Artículos - Geología |
Cargar archivos:
| Fichero | Tamaño | Formato | |
|---|---|---|---|
| 166751.pdf | 5.17 kB | Adobe PDF | Visualizar/Abrir |